10 Most asked Questions from Java Programmers

Hope you liked my previous post “Top 25 Interview Questions”. Here comes the next 10.

1) Design discussion on elevator.
Hint: Ask questions related to elevator functionality; come up with a High Level design and Low level design. Be prepared for scheduling questions related to elevator.

2) “n” points are given , find the number of quadruplets which form square.

3) Questions related to memory management in Java.

4) Mark and sweep algorithm and garbage collection in Java

5) Construct tree from Inorder and Preorder

6) Serialization in Java

7) How to ensure that instance is never garbage collected?
Hint: We can use singleton pattern. There’s a static reference to a singleton, so it won’t be eligible for garbage collection until the classloader is eligible for garbage collection.

8) Questions related to classloader, rt.jar?

9) Difference between String, StringBuffer and StringBuilder?

10) Why String is immutable in Java?
Note: Do discuss about security related issues in class loader.

• Read More- Java Articles
• MCQ Quizzes of Java

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This article is contributed by Rishi Verma. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.

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